1. Field of the Invention
The present invention relates, in general, to an emergency power supply system for a fuel cell-powered vehicle and, more particularly, to an emergency power supply system for a fuel cell-powered vehicle, which, when a low voltage DC-DC converter (LDC) has a continuous operational problem during running of a fuel cell-powered vehicle, keeps a fuel cell activated using a DC-DC converter provided within a high voltage electronic appliance, thereby maintaining continuous running of the fuel cell-powered vehicle.
2. Description of the Related Art
Generally, a low voltage battery in a fuel cell-powered vehicle serves as both a power source of main controllers of a fuel cell system, such as fuel cell unit (FCU), motor control unit (MCU), etc., and a power source of e.g. an air conditioner in a vehicle. Further, the low voltage battery is an essential element to initially start a vehicle.
As such, a fuel cell-powered vehicle is driven in such a manner that, after a fuel cell is operated with an initially-generated high voltage, a low voltage battery is continuously charged with a low voltage converted by a low voltage DC-DC converter (LDC). However, when the LDC has an operational problem during running of a fuel cell-powered vehicle so as not to continuously supply power, the fuel cell-powered vehicle stops running due to discharge of the low voltage battery.
If this occurs when a vehicle is being driven, even with sufficient supply of high voltage energy for driving of a vehicle, a supply of power from the low voltage battery is interrupted, disabling running operations and re-start of the vehicle.
The foregoing is intended merely to aid in the understanding of the background of the present invention, and is not intended to mean that the present invention falls within the purview of the related art that is already known to those skilled in the art.